The present disclosure is related generally to the field of orthodontics. More particularly, the present disclosure is related to using an individualized orthodontic treatment index.
Some objectives in the field of orthodontics are to realign a patient's teeth to positions where the teeth function well and align the teeth to provide a pleasing aesthetic appearance. One goal of an orthodontic treatment professional is to take the patient's dentition from a starting arrangement to a final arrangement.
Further, when using fixed brackets and wires (i.e., braces) may be applied to a patient's teeth to gradually reposition them from an initial arrangement to a final arrangement. The diagnosis and treatment planning process of orthodontic cases may be imprecise as the final dentition of a patient may be based on the knowledge and expertise of the treatment professional in assembling various parameters in an assessment of each patient's condition and in a determination of a final position for each tooth. Different treatment professionals may vary in their definitions of individual orthodontic parameters and their definition of how a case should ideally be treated may also vary.
To overcome some of these subjective issues, various indices have been used to more objectively define a patient's dentition, including initial dentition, progress dentition, and final outcome dentition. For example, the PAR (Peer Assessment Rating) index identifies how far a dentition is from a good occlusion. A score is assigned to various occlusal traits which make up a malocclusion. The individual scores are summed to obtain an overall total, representing the degree a case deviates from ideal functional alignment and occlusion. The PAR score is then calibrated to a known standard set of orthodontic conditions so this individual is able to rate new cases similarly. The PAR score may be weighted or unweighted, depending on the relative importance of certain components of the occlusion.
In PAR, a score of zero would indicate ideal alignment and positioning of all orthodontic dental components, as defined by generally accepted occlusal and aesthetic relationships the orthodontic community has adopted. Higher scores would indicate increased levels of irregularity. The PAR score can be recorded on pre-, mid- and/or post-treatment dental casts. The difference between any two of these scores represents the degree of improvement as a result of orthodontic intervention during the represented portion of treatment. The score may be represented as an absolute point improvement or as a percentage improvement with respect to an earlier treatment point used for the comparison.
In addition to the PAR index, other indices may be used such as Index of Complexity Outcome and Need (ICON), Index of Orthodontic Treatment Need (IOTN) and American Board of Orthodontics (ABO) indices. These indices also rely on individual dental measurements in order to derive an assessment of deviation from an ideal. One drawback to using such indices is that the individual dental measurements may be based on landmarks that are identified on the patient's dentition by a treatment professional. After identifying landmarks at an earlier stage of treatment, the treatment professional may not be able to accurately identify the same landmarks at a later stage of treatment because the patient's dentition may have changed during the course of treatment.